GB1053753A - - Google Patents

Abstract

1,053,753. Bending and tempering glass sheets. LIBBEY-OWENS-FORD GLASS CO. Sept. 4, 1963 [Sept. 14, 1962], No. 34923/63. Heading C1M [Also in Division B8] In a method of bending and tempering glass sheets the latter are moved along a predetermined path through a zone where they are heated to softening point, then advanced at a set speed to a set location in a bending zone where they are halted and pressure applied to the opposite surfaces to bend the sheet, the bent sheet is moved out of the bending zone and into a chilling zone at a speed relatively greater than the speed of entry into the bending zone, this speed being reduced to the first entry speed when the sheets have entered the chilling zone. A glass sheet 12 is passed on a conveyer 11 through a furnace 16 wherein it is heated to its softening point (Fig. 1, not shown). On leaving the heating zone the sheet is passed into a bending zone by means of entry roller conveyer 27 which is driven at the same speed as conveyer 11. The sheet is then passed on to rollers 91 of the bending zone at the end of which the leading edge of the sheet contacts the stop butt 119 of a device 29 which applies a brake 107 on a twospeed motor 96 driving rollers 91. The device 29 is lowered into position when the sheet is sensed to be approaching by means 28 e.g. photoelectric cell. In this arrested position the sheet is lifted vertically away from the rolls 91 by the complementary shaped lower mould half 25 being brought into contact with the upper mould half 24 and the sheet bent to the desired shape. The lower mould half 25 is raised by the actuation of a magnetic clutch starting a cam 63 which has a follower 73 fixed to a parallel links system attached to the lower mould half carriage 52. The cam 63 also determines the length of time bending pressure is applied. When the now bent sheet has been lowered on to the rollers 91 the motor system 96 is actuated to drive the rolls at a higher speed than the entry speed, the stop device 29 is raised to an inoperative position by piston and cylinder means 134, 135, and the bent sheet is advanced into the chilling zone between blowers 20, 21. The sheet is passed along take out rolls 112 which are driven by the same motor and at the same speed as rolls 91. When the sheet has entered the chilling area upon rolls 22a the driving speed is reduced to that of the entry speed from the heating zone A. The piston and cylinder means 134, 135 are then reversed and the stop device 29 is lowered to start a new sequence.